The present invention concerns a solid state laser comprising a rigid base, a laser head including a laser rod having a longitudinal axis and an optical pumping lamp coupled to said laser rod, and means for connecting said laser head to said base.
As will be evident from the following description, the laser according to the present invention may be either an oscillating laser or an amplifying laser.
The first type as is well known includes two mirrors, at least one of which is partially transparent, arranged along and on either side of the laser rod's axis to define a resonance cavity.
The second type does not have such mirrors.
In such lasers, the pumping lamp of the laser rod must be replaced quite frequently because it wears rapidly and sometimes even breaks.
This lamp has an elongated shape and is arranged in the laser head with its longitudinal axis parallel to that of the laser rod.
Moreover, this lamp is fixed in the laser head by its two ends which pass through suitable openings provided in the walls of the laser head.
To replace this lamp, it must thus be slid through one of these openings in a direction parallel to the axis of the laser rod.
In a laser, however, the optical elements such as the aforementioned mirrors or lenses are usually arranged along the axis of the laser rod spaced apart from the laser rod by distances which are less than the length of the pumping lamp, and these optical elements or their supports often obstruct complete removal of the pumping lamp from the laser head.
Mostly therefore to be able to replace the pumping lamp, the laser head or one or more of these optical elements must be completely removed from the base on which they are secured.
Such dismantling has the drawback that all adjustments of the position of the various components of the laser required for its correct operation must be made once again after each replacement of the pumping lamp. These adjustments are delicate and require much time.
Moreover, the laser head usually has a duct in which a cooling fluid such as water flows to remove heat produced during operation of the laser, and a portion of this duct surrounds the pumping lamp.
If the laser head is dismantled to allow replacement of the pumping lamp, this piping must of course be disconnected before the dismantling operation and must be reconnected after the laser head has been replaced.
During these operations of disconnecting and reconnecting the piping, it is possible that some cooling fluid may flow onto the laser base or other elements of the laser and this may lead to corrosion of the base and/or elements. It is also possible that this fluid produces short-circuits between elements located on this base and which are at different potentials during operation of the laser.
Moreover, in any event, some fluid may also escape from the laser head when the lamp is slid out of its cavity, with the same consequences as above.
It is sometimes possible to configure one of the supports for the optical elements arranged along the axis of the laser rod such that it does not obstuct replacement of the pumping lamp, for example by providing in this support an opening of suitable size and location.
There is therefore no need then to make the aforementioned adjustments each time the lamp is changed, but cooling fluid is still liable to flow onto the laser base.
Furthermore, if the pumping lamp has to be replaced not because it is worn but because it is broken, it is in any event necessary to separate the laser head from the laser base, with the drawbacks set out above, because otherwise it would not be possible to adequately clean the lamp's socket and remove all of the debris therefrom.
In currently-available lasers of the above-defined type, the laser head is directly fixed to the base.
A part of the heat produced during operation of the laser is consequently transmitted to this base, even if the laser head is cooled in the above-described manner.
This results in local heating and deformation of the laser base. As the other components of the laser and in particular the optical parts are also fixed to the base, this deformation leads to a variation in the position of these parts relative to one another and to the laser head.
This variation may disturb operation of the laser or may even cause it to break down.
An object of the present invention is to propose a laser of the above defined type which does not have the described drawbacks, i.e. in which replacement of the pumping lamp is easy, requires no readjustment of the various components of the laser and may, in relevant cases, be carried out without any cooling fluid dripping on the base or on any other part of the laser.
This object is achieved due to the fact that, in the claimed laser, the means for connecting the laser head to the laser base comprise a hinge enabling this head to be pivoted relative to the base about an axis of rotation substantially parallel to the axis of the laser rod.